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pcm_utils: moved code to pcm_resample.c

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Separate the resampling code from the rest of pcm_utils.c.  Create two
sub-libraries: pcm_resample_libsamplerate.c and
pcm_resample_fallback.c.
This commit is contained in:
Max Kellermann
2008-10-23 20:00:51 +02:00
parent 098991f8e8
commit 6b1c54ef96
8 changed files with 308 additions and 176 deletions
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168
src/pcm_utils.c
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@@ -209,166 +209,10 @@ void pcm_convert_init(struct pcm_convert_state *state)
{
memset(state, 0, sizeof(*state));
pcm_resample_init(&state->resample);
pcm_dither_24_init(&state->dither);
}
#ifdef HAVE_LIBSAMPLERATE
static int pcm_resample_get_converter(void)
{
const char *conf = getConfigParamValue(CONF_SAMPLERATE_CONVERTER);
long convalgo;
char *test;
const char *test2;
size_t len;
if (!conf) {
convalgo = SRC_SINC_FASTEST;
goto out;
}
convalgo = strtol(conf, &test, 10);
if (*test == '\0' && src_get_name(convalgo))
goto out;
len = strlen(conf);
for (convalgo = 0 ; ; convalgo++) {
test2 = src_get_name(convalgo);
if (!test2) {
convalgo = SRC_SINC_FASTEST;
break;
}
if (strncasecmp(test2, conf, len) == 0)
goto out;
}
ERROR("unknown samplerate converter \"%s\"\n", conf);
out:
DEBUG("selecting samplerate converter \"%s\"\n",
src_get_name(convalgo));
return convalgo;
}
#endif
#ifdef HAVE_LIBSAMPLERATE
static size_t pcm_resample(int8_t channels, uint32_t inSampleRate,
const int16_t *src, size_t src_size,
uint32_t outSampleRate, int16_t *outBuffer,
size_t outSize,
struct pcm_convert_state *convState)
{
static int convalgo = -1;
SRC_DATA *data = &convState->data;
size_t dataInSize;
size_t dataOutSize;
int error;
if (convalgo < 0)
convalgo = pcm_resample_get_converter();
/* (re)set the state/ratio if the in or out format changed */
if ((channels != convState->lastChannels) ||
(inSampleRate != convState->lastInSampleRate) ||
(outSampleRate != convState->lastOutSampleRate)) {
convState->error = 0;
convState->lastChannels = channels;
convState->lastInSampleRate = inSampleRate;
convState->lastOutSampleRate = outSampleRate;
if (convState->state)
convState->state = src_delete(convState->state);
convState->state = src_new(convalgo, channels, &error);
if (!convState->state) {
ERROR("cannot create new libsamplerate state: %s\n",
src_strerror(error));
convState->error = 1;
return 0;
}
data->src_ratio = (double)outSampleRate / (double)inSampleRate;
DEBUG("setting samplerate conversion ratio to %.2lf\n",
data->src_ratio);
src_set_ratio(convState->state, data->src_ratio);
}
/* there was an error previously, and nothing has changed */
if (convState->error)
return 0;
data->input_frames = src_size / 2 / channels;
dataInSize = data->input_frames * sizeof(float) * channels;
if (dataInSize > convState->dataInSize) {
convState->dataInSize = dataInSize;
data->data_in = xrealloc(data->data_in, dataInSize);
}
data->output_frames = outSize / 2 / channels;
dataOutSize = data->output_frames * sizeof(float) * channels;
if (dataOutSize > convState->dataOutSize) {
convState->dataOutSize = dataOutSize;
data->data_out = xrealloc(data->data_out, dataOutSize);
}
src_short_to_float_array((const short *)src, data->data_in,
data->input_frames * channels);
error = src_process(convState->state, data);
if (error) {
ERROR("error processing samples with libsamplerate: %s\n",
src_strerror(error));
convState->error = 1;
return 0;
}
src_float_to_short_array(data->data_out, (short *)outBuffer,
data->output_frames_gen * channels);
return data->output_frames_gen * 2 * channels;
}
#else /* !HAVE_LIBSAMPLERATE */
/* resampling code blatantly ripped from ESD */
static size_t pcm_resample(int8_t channels, uint32_t inSampleRate,
const int16_t *src, mpd_unused size_t src_size,
uint32_t outSampleRate, char *outBuffer,
size_t outSize,
mpd_unused struct pcm_convert_state *convState)
{
uint32_t rd_dat = 0;
uint32_t wr_dat = 0;
const int16_t *in = (const int16_t *)src;
int16_t *out = (int16_t *)outBuffer;
uint32_t nlen = outSize / 2;
int16_t lsample, rsample;
switch (channels) {
case 1:
while (wr_dat < nlen) {
rd_dat = wr_dat * inSampleRate / outSampleRate;
lsample = in[rd_dat++];
out[wr_dat++] = lsample;
}
break;
case 2:
while (wr_dat < nlen) {
rd_dat = wr_dat * inSampleRate / outSampleRate;
rd_dat &= ~1;
lsample = in[rd_dat++];
rsample = in[rd_dat++];
out[wr_dat++] = lsample;
out[wr_dat++] = rsample;
}
break;
}
return outSize;
}
#endif /* !HAVE_LIBSAMPLERATE */
static void
pcm_convert_channels_1_to_2(int16_t *dest, const int16_t *src,
unsigned num_frames)
@@ -542,11 +386,11 @@ size_t pcm_convert(const struct audio_format *inFormat,
assert(dest_size >= len);
memcpy(outBuffer, buf, len);
} else {
len = pcm_resample(outFormat->channels,
inFormat->sample_rate, buf, len,
outFormat->sample_rate,
(int16_t*)outBuffer,
dest_size, convState);
len = pcm_resample_16(outFormat->channels,
inFormat->sample_rate, buf, len,
outFormat->sample_rate,
(int16_t*)outBuffer,
dest_size, &convState->resample);
if (len == 0)
exit(EXIT_FAILURE);
}